Systems are known that electrolyze water containing ionic species (e.g., alkali salts) to produce acidic electrolyzed water and alkaline electrolyzed water. Acidic electrolyzed water can be is a strong sterilizing agent that is increasingly used in a variety of sanitizing applications including in the medical, agricultural and food processing industries and in other institutional environments. The alkaline or basic electrolyzed water also has a detergent effect and is useful in many cleaning applications. Sodium chloride is commonly used as the alkali salt that is dissolved in the water because it produces acids and bases that are environmentally friendly, potent and low in cost.
Commercially available electrolyzing water systems have a number of drawbacks. Large commercial users of such systems can require significant quantities of electrolyzed water on a daily basis. Since most available electrolyzing systems are relatively slow in processing the electrolyzed alkaline and acidic water, producing large quantities can be tedious and time consuming, sometimes resulting in inadequate supply for the commercial needs. While increased production can be achieved by increasing the number of electrolyzing cell pairs pursuant to existing cell designs, such approach proportionally increases the cost of the system. Moreover, many commercial users require significantly more alkaline cleaners than acid sanitizers. Since both are electrolyzed simultaneously, to produce sufficient quantities of the cleaner, excessive amounts of the sanitizer produced often must be discarded.
The contents (e.g., impurities) of water directed to the electrolyzer system can further effect the quality of the processed alkaline and acidic electrolyzed water. Under some conditions, to achieve an optimum pH of the alkaline cleaner, the acidic electrolyzed water (the sanitizer) can have such a low pH that the acid is unstable for safe or effective use. To correct that problem, the pH of the alkaline cleaner can be undesirably affected.
Moreover, if the ion permeable membranes of the electrolyzing cells of the system are not assembled and maintained in certain spatial relation (e.g., parallel relation) to the electrode plates, the electrolyzing process again can be altered. Similarly, if the pressure of liquid through the electrolyzer cell is increased in an effort to increase the processing rate, alignment of the membrane can be distorted with resulting inadequate ion exchange. The increased flow rate through the cell at higher liquid pressures further can limit the time for adequate ion exchange. Increasing the power supply to the electrode cells to increase production also can adversely affect the pH of the alkali or acidic electrolyzed waters.